New York: Those with vitamin D deficiency from birth to early childhood may be at 60 per cent higher risk of elevated systolic blood pressure between ages 6 and 18, says a study.

Systolic refers to the first or top number in a blood pressure reading. High systolic blood pressure readings increase the risk of cardiovascular disease even when diastolic blood pressure, the second number in a blood pressure reading, is controlled.

"Our findings raise the possibility that screening and treatment of vitamin D deficiency with supplementation during pregnancy and early childhood might be an effective approach to reduce high blood pressure later in life," said lead author Guoying Wang, Assistant Scientist at Johns Hopkins University Bloomberg School of Public Health in Baltimore, Maryland, US.

For the study, the researchers followed 775 children from birth to age 18 at the Boston Medical Center.

Low vitamin D levels were defined as less than 11 ng/ml (nanograms per millimetre) in cord blood at birth and less than 25 ng/ml in a child's blood during early childhood.

Vitamin D is needed for the body to absorb calcium for strong bones. It is made by our bodies when we are exposed to sunlight and found in a few foods, such as eggs, salmon and fortified milk products. It is also available as a vitamin supplement.